What is the CGS unit of thermal conductivity?

Why electric cables are always kept sagging instead of stretching?

Why metre scale is made by invar?

What will happen if a mercury thermometer is suddenly put in a hot-water trough? Why?

What are the main uses of bimetallic strip?

How thermal conductivity can be defined?

How would you explain that different materials conduct heat differently? What is meant by thermal conductivity?

What is the meaning of the statement? $\alpha =19\times {10}^{-6} {\mathrm{K}}^{-1}$ for brass. Write the mathematical expression of coefficient of apparent expansion. State its SI unit.

What is thermal resistivity? State and explain its analogy with electrical resistivity.